I have a powerbook 15" with an airport extreme card. My roomates all have pc's with wireless cards too. My signal is weak as heck when im not in the same room as the router, yet my companions all have excellent signals with further away desktops. I can pick up like 3 different neighbor signals with almost the same strength as ours, AND ive had excellent signals from different sources in the past. What could possibly be the problem here? Our router? my card? hmm.... It's very frustrating being a mac noob.